i. Field of the Invention
This invention relates to roller skates of the type having a single central front roller and a single central rear roller disposed in tandem.
II. Description of the Prior Art
In roller skates of the above mentioned type, problems exist in providing a skate having a pleasing aesthetic appearance as well as one which would have sufficient strength and provide easy running and proper manoeuverability. Thus, in order to provide a roller skating device of the above mentioned type, previous patentees have resorted to various expediencies in order to provide the proper stability. For example H.L. True, in U.S. Pat. No. 251,321, patented Dec. 20, 1881, and A. J. Kennedy, in U.S. Pat. No. 979,169, patented Dec. 20, 1910, provided complicated and awkward stabilizing devices between the bottom of the skate and the ankle of the wearer of the skate. This was not entirely satisfactory, as it still did not provide a skate having both sufficient stability and a pleasing aesthetic appearance.
The problem of noisy operation was attempted to be solved in Canadian Pat. No. 132,398, patented Apr. 11, 1911, in the name of Jan Zverina, in which non-rotary axles were mounted in brackets and tubular roller hubs were revolvably mounted on the axles and were provided with lateral passages and pneumatic tires mounted on the hubs with inflation valves located in the passages. This obviously suffered the disadvantages inherent in the use of pneumatic tires with respect to duration of operability.
The problem of monoeuverability was attempted to be solved in U.S. Pat. No. 2,122,311, patented June 28, 1938, in the name of William R. Campbell, the skate included a trailing front roller, that is, the horizontal axis of the roller was located in the rear of the vertical axis of the roller frame, the front roller being of the ball bearing castor-type so that when the skater turned on the edge of the skate, the roller would swivel and facilitate movement of the skate when moving in a curved direction of travel. While this was satisfactory on smooth surfaces, the use of a castor-type wheel obviously was unsatisfactory for uneven surfaces or unpaved roads or other such surfaces or hard packed grassy hills, etc.
An attempt to improve the stability of the skate was provided by U.S. Pat. No. 2,529,314, of Nov. 7, 1950, in the name of Max Wilhelm Schmid, wherein the wheels or rollers of the device had ball shaped or spherical running surfaces and were supported relatively to the plate platform or the like by means of axle forks which were so shaped that the lower parts would be disposed together with the securing means in the outer ends of the bearing bushings or hubs carried by the rollers, with the bushings or hubs being recessed within the rollers and the arrangement being such that the maximum inclination of the device may be obtained when taking curves, performing arcs or figures or the like. A deficiency of this particular structure, however, was the lack of sufficient stabilisers to support the ankle of the wearer, as well as the excessive weight of the ball shaped or spherical rollers.
It was attempted, in U.S. Pat. No. 2,719,724, of R. Lundgren, patented Oct. 4, 1955, to provide a roller mounted device, more particularly a floating axle roller skate which can be easily steered by a skater. A deficiency of this particular device resided in the fact that a offset castor effect was provided, thereby making it difficult to skate on hard packed, unpaved roads or on hard packed grassy hills and slopes. In addition, the rollers were substantially cylindrical solid rubber rollers, and the means of supporting the shoe to the base plate was not sufficient to provide a suitable and sufficient support for the ankles of the wearer.
The problem of providing a skating device for skating on various land surfaces in a comparatively silent and noiseless manner, was provided in Canadian Pat. No. 772,304, issued Nov. 21, 1967, in the name of Eric H. Bown, by providing a skating device with an extensible floor to support the feet of the operator, with spherical or globular shaped balls adequately secured below the extensible floor and secured in a tandem manner, with specific provision being made for stabilising the ankles of the wearer. However, a deficiency of this type of device, was the excessive weight of the solid globular rollers.
The problem of providing a skate structure which would increase the speed of manoeuverability of the skates, was attempted to be solved in U.S. Pat. No. 3,501,162, patented Mar. 17, 1970, in the name of Dean W. Toone, by providing for variation in camber as the wheel turns. However, a suitable securement of the shoe of the user to the roller skate construction was not provided in a manner which would provide the necessary stability.
British Pat. No. 741,159, provided roller skates including a foot plate or platform at the underside of which were two supporting rollers of spheroidal shape mounted in tandem, and also provided a means for pivotally moving the brackets supporting the spheroidal shaped rollers relative to the plate about an axis located on the longitudinal center line of the plate. However, a difficulty of this patent resides in the fact that the spherical rollers are of a solid rubber, thereby adding excessive weight to the skating device. In addition no sufficient means were provided for adequately supporting the shoes of the user on the skate.
Finally, the problem of providing adequate steerability to the skate was attempted to be solved in Canadian Pat. No. 933,967, patented Sept. 18, 1973, in the name of Paul F. Steinhiser, in which the bracket supporting the wheels was pivotally mounted intermediate the wheels in contact with the body about a pivot axis intersecting the longitudinal axis of the plane and spaced from the axle with the steering means including resilient spring means seated on the bracket for yieldably resisting pivotal displacement by unbalanced lateral pressure on the wheel. However, adequate support to provide sufficient stability to the user, was not provided.